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A291976 a(n) = (4*n)! * [z^(4*n)] exp(1 - (cos(z) + cosh(z))/2). 4
1, -1, 34, -5281, 2185429, -1854147586, 2755045819549, -6440372006517541, 21861211462545555394, -100916681831006840635021, 596756926975162013357972089, -4237398636260867429185819175026, 32919774165127854788267224335178009 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Alternating row sums of A291452.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..155

MAPLE

A291976 := proc(n) exp(1 - (cos(z) + cosh(z))/2):

(4*n)!*coeff(series(%, z, 4*(n+1)), z, 4*n) end:

seq(A291976(n), n=0..12);

# second Maple program:

b:= proc(n, t) option remember; `if`(n=0, 1-2*t, add(

      b(n-4*j, 1-t)*binomial(n-1, 4*j-1), j=1..n/4))

    end:

a:= n-> b(4*n, 0):

seq(a(n), n=0..20);  # Alois P. Heinz, Aug 14 2019

CROSSREFS

Cf. A291452.

Sequence in context: A209943 A187708 A231084 * A212035 A292750 A199837

Adjacent sequences:  A291973 A291974 A291975 * A291977 A291978 A291979

KEYWORD

sign

AUTHOR

Peter Luschny, Sep 07 2017

STATUS

approved

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Last modified April 4 08:58 EDT 2020. Contains 333213 sequences. (Running on oeis4.)